• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.63-67
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• 2003

Mercury, one of the most diffused and hazardous organ-specific environmental contaminants, exists in a wide variety of physical and chemical states. Although the reports indicate that the mercury induces a deleterious damage, little has been known from the investigations of its effects in living organisms. The purpose of this study is to evaluate the effects of mercury chloride and ionizing radiation. Prepubertal male F344 rats were administered mercury chloride in drinking water throughout the experimental period. Two weeks after whole body irradiation, organs were collected to analyze the induced injury. Serum levels of GOT, GPT, ALP, and LDH were checked in the experimental groups and the hematological analysis was accomplished in plasma. In conclusion, the target organ of mercury chloride seems to be urinary organs and the pattern of damage induced by mercury differs from that by irradiation.

• Journal of the Korean Society for Precision Engineering
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• v.7 no.2
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• pp.113-123
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• 1990

To study deleterious effects of contaminants contained in lubricating systems, the effects of fine alumina particle concentration and size on the critical failure load, friction and wear characteristic were examined on boundary lubrication condition using the four ball machine. The following conclusions are deduced: The abrasive is found to cause a transition from mild wear to severe wear at less severe conditions than with clean oil. In mild wear region the friction and wear increase with particle size and concentration, but in severe wear region do not exhibit any definite trend. In relation to film thinckness there is a threshold of particle size beyond which the failure load no longer decreases with particle size.

• Clinical and Experimental Reproductive Medicine
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• v.46 no.3
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• pp.99-106
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• 2019

Bisphenol A (BPA) is an endocrine-disrupting chemical that is capable of interfering with the normal function of the endocrine system in the body. Exposure to this chemical from BPA-containing materials and the environment is associated with deleterious health effects, including male reproductive abnormalities. A search of the literature demonstrated that BPA, as a toxicant, directly affects the cellular oxidative stress response machinery. Because of its hormone-like properties, it can also bind with specific receptors in target cells. Therefore, the tissue-specific effects of BPA mostly depend on its endocrine-disrupting capabilities and the expression of those particular receptors in target cells. Although studies have shown the possible mechanisms of BPA action in various cell types, a clear consensus has yet to be established. In this review, we summarize the mechanisms of BPA action in spermatozoa by compiling existing information in the literature.

• Structural Engineering and Mechanics
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• v.87 no.3
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• pp.283-296
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• 2023

Free-vibration and buckling analyses of plate problems are investigated with the aid of the strain gradient notation finite element method (SGN-FEM). As SGN-FEM employs physically interpretable polynomials in developing finite elements, parasitic shear sources, which are the cause of shear locking, can be precisely identified and subsequently eliminated. This allows two mutually complementary objectives to be defined in this work, namely, evaluate the efficiency of free-vibration and buckling results provided by corrected models, and study the severity of parasitic shear effects on plate models performance. Parasitic shear are flexural terms erroneously present in shear strain polynomials. It is reviewed here that six parasitic shear terms arise during the formulation of the four-node Mindlin plate element. Two parasitic shear terms have been identified in the in-plane shear strain polynomial while other two have been identified in each of the transverse shear strain polynomials. The element is corrected a-priori, i.e., during development, by simply removing the spurious terms from the shear strain polynomials. The computational implementation of the element in its two versions, namely, containing the parasitic shear terms (PS) and corrected for parasitic shear (SG), allows for assessments of the accuracy of results and of the deleterious effects of parasitic shear in free vibration and buckling analyses. This assessment of the parasitic shear effects is a novelty of this work. Validation of the SG model is done comparing its results with analytical results and results provided by other numerical procedures. Analyses are performed for square plates with different thickness-to-length ratios and boundary conditions. Results for thin plates provided by the PS model do not converge to the correct solutions, which indicates that parasitic shear must be eliminated. That is, analysts should not rely on refinement alone. For thick plates, PS model results can be considered acceptable as deleterious effects are really critical in thin plates. On the other hand, results provided by the SG model converge well for both thin and thick plates. The effectiveness of the SG model is established via high-accuracy results obtained in several examples. It is concluded that corrected SGN-FEM models are efficient alternatives for free-vibration and buckling analysis of Mindlin plate problems, and that precise elimination of parasitic shear is a requirement for sound analyses.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.1
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• pp.15-21
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• 2007

Three newly authorized bivoltine silkworm hybrids namely, $CSR2{\times}CSR4$ (productive single hybrid), $(CSR6{\times}CSR26){\times}(CSR2{\times}CSR27)$ (productive double hybrid) and $CSR18{\times}CSR19$ (robust single hybrid) were chosen for the present study. These hybrids were subjected to different temperature and humidity treatments i.e., $25{\pm}$1^{\circ}C and RH $65{\pm}5%$ (control), $30{\pm}1^{\circ}C$, with combinations of low relative humidity (RH $65{\pm}5%$) and high RH ($85{\pm}5%$) at different stages during rearing and spinning of silkworm larvae. The larvae of after 3rd moult were subjected to different thermal and humidity stress till the assessment of cocoon traits. The comparative rearing and reeling performance clearly indicated that the deleterious effect of high temperature and high RH was more pronounced for the majority of traits such as cocoon uniformity, cocoon weight, shell weight, shell percentage, reelability, filament length, raw silk percentage raw silk recovery denier and waste percentage on silk weight than other temperature and RH treatments and this effect was almost similar for all three silkworm hybrids studied. The present investigation clearly indicate that the deleterious effect of high temperature and high RH was more pronounced on rearing and spinning of silkworm larvae than other temperature and RH treatments and similar effect was noticed for all the three silkworm hybrids studied. The cocoon characters can be improved by providing ideal environmental conditions even during spinning stage of larvae affected with high temperature and RH. The study also suggest that high temperature and low humidity has greater effect during rearing stage than spinning stage.

• Journal of Communications and Networks
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• v.15 no.6
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• pp.559-568
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• 2013

We report on the first error-free terahertz (THz) wireless communication at 0.310 THz for data rates up to 8.2 Gbps using a 18-GHz-bandwidth GaAs/AlGaAs field-effect transistor as a detector. This result demonstrates that low-cost commercially-available plasma-wave transistors whose cut-off frequency is far below THz frequencies can be employed in THz communication. Wireless communication over 50 cm is presented at 1.4 Gbps using a uni-travelling-carrier photodiode as a source. Transistor integration is detailed, as it is essential to avoid any deleterious signals that would prevent successful communication. We observed an improvement of the bit error rate with increasing input THz power, followed by a degradation at high input power. Such a degradation appears at lower powers if the photodiode bias is smaller. Higher-data-rate communication is demonstrated using a frequency-multiplied source thanks to higher output power. Bit-error-rate measurements at data rates up to 10 Gbps are performed for different input THz powers. As expected, bit error rates degrade as data rate increases. However, degraded communication is observed at some specific data rates. This effect is probably due to deleterious cavity effects and/or impedance mismatches. Using such a system, realtime uncompressed high-definition video signal is successfully and robustly transmitted.

• Mycobiology
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• v.45 no.4
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• pp.240-254
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• 2017

Cereal grains are the most important food source for humans. As the global population continues to grow exponentially, the need for the enhanced yield and minimal loss of agricultural crops, mainly cereal grains, is increasing. In general, harvested grains are stored for specific time periods to guarantee their continuous supply throughout the year. During storage, economic losses due to reduction in quality and quantity of grains can become very significant. Grain loss is usually the result of its deterioration due to fungal contamination that can occur from preharvest to postharvest stages. The deleterious fungi can be classified based on predominance at different stages of crop growth and harvest that are affected by environmental factors such as water activity ($a_w$) and eco-physiological requirements. These fungi include species such as those belonging to the genera Aspergillus and Penicillium that can produce mycotoxins harmful to animals and humans. The grain type and condition, environment, and biological factors can also influence the occurrence and predominance of mycotoxigenic fungi in stored grains. The main environmental factors influencing grain fungi and mycotoxins are temperature and $a_w$. This review discusses the effects of temperature and $a_w$ on fungal growth and mycotoxin production in stored grains. The focus is on the occurrence and optimum and minimum growth requirements for grain fungi and mycotoxin production. The environmental influence on aflatoxin production and hypothesized mechanisms of its molecular suppression in response to environmental changes are also discussed. In addition, the use of controlled or modified atmosphere as an environmentally safe alternative to harmful agricultural chemicals is discussed and recommended future research issues are highlighted.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.2
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• pp.290-296
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• 2019

Objective: Pigs share many physiological, anatomical and genomic similarities with humans, which make them suitable models for biomedical researches. Understanding the genetic status of Yucatan miniature pigs (YMPs) and their association with human diseases will help to assess their potential as biomedical model animals. This study was performed to identify non-synonymous single nucleotide polymorphisms (nsSNPs) in selective sweep regions of the genome of YMPs and present the genetic nsSNP distributions that are potentially associated with disease occurrence in humans. Methods: nsSNPs in whole genome resequencing data from 12 YMPs were identified and annotated to predict their possible effects on protein function. Sorting intolerant from tolerant (SIFT) and polymorphism phenotyping v2 analyses were used, and gene ontology (GO) network and Kyoto encyclopedia of genes and genomes (KEGG) pathway analyses were performed. Results: The results showed that 8,462 genes, encompassing 72,067 nsSNPs were identified, and 118 nsSNPs in 46 genes were predicted as deleterious. GO network analysis classified 13 genes into 5 GO terms (p<0.05) that were associated with kidney development and metabolic processes. Seven genes encompassing nsSNPs were classified into the term associated with Alzheimer's disease by referencing the genetic association database. The KEGG pathway analysis identified only one significantly enriched pathway (p<0.05), hsa04080: Neuroactive ligand-receptor interaction, among the transcripts. Conclusion: The number of deleterious nsSNPs in YMPs was identified and then these variants-containing genes in YMPs data were adopted as the putative human diseases-related genes. The results revealed that many genes encompassing nsSNPs in YMPs were related to the various human genes which are potentially associated with kidney development and metabolic processes as well as human disease occurrence.

• Archives of Pharmacal Research
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• v.20 no.1
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• pp.34-38
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• 1997

Recombinant human epidermal growth factor (rhEGF), a polypeptide of 53 amino acid residues, is subject to degradation by numerous enzymes, especially proteases, when it is applied on the skin for the treatment of open wound. Amastatin, aprotinin, bestatin, EDTA, EGTA, gabexate, gentamicin, leupeptin, and TPCK were investigated for the possible protease inhibitors, which may use to protect rhEGF from degradation by the enzymes in the skin. Skin homogenates containing protease inhibitors and rhEGF were incubated at $37^{\circ}C$ for 30 minutes. After the reaction was stopped with trifluoroacetic acid, the amount of rhEGF remaining in the sample was determined with an HPLC method. The percentages of rhEGF degraded, at the skin/PBS ratio of 0.25, in the mouse, rat, and human skin homogenate were 85%, 70%, and 46%, respectively. The degree of degradation of rhEGF in the cytosolic fraction was higher than that in the membrane fraction and these enzyme reactions were completed in 30 minutes. Bestatin, EGTA, and TPCK showed significant inhibitory effects on the degradation of rhEGF in the two fractions (p<0.05), while the other protease inhibitors had no significant inhibitory effects or, even resulted in deleterious effects. Therefore, the formulation containing one or several inhibitors among these effective inhibitors would be a promising topical preparation of rhEGF for the treatment of open wound.

• Advances in environmental research
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• v.1 no.2
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• pp.109-123
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• 2012

Our study investigated the effects of Solanum macrocarpon (African eggplant) on haematological and biochemical parameters of male albino rats exposed to urban air pollution ($O_3$, $PM_{10}$, CO, $SO_2$, $NO_2$ and VOC). Male albino Wistar rats were exposed for 63 days either to urban air pollution without treatment (A); oral supplementation with Solanum macrocarpon given at 36 and 75 mg/kg body weight (BW), representing C and D respectively and exposed to air pollution; oral supplementation with Solanum macrocarpon given at 75 mg/kg BW after exposure to air pollution (B); or kept in animal house without exposure to air pollution (E). Animals exposed to air pollution showed significant alterations in haematological and biochemical parameters signaling that the blood and organs were badly injured. There were significant elevations in white blood cells (WBC) and its indices, reduction in red blood cells (RBC) and significant depletions of non-enzymic antioxidants, total protein and increase in lipid peroxidation values. Solanum macrocarpon supplementation in the feed of animals halted significantly the deleterious effects of air pollution, with co-administration during exposure given better results.